A study of the end-plate potential in sodium deficient solution.
1. The effect of anticholinesterases in lengthening the end-plate potential is much more pronounced in a low-sodium solution than in an ordinary Ringer-curare solution.2. To investigate this difference, intracellular recordings of end-plate potentials and of end-plate currents in voltage-clamped muscle fibres were used.3. It was found that the very large lengthening of the end-plate potential in a low-sodium solution was due to a combination of three factors: (i) lengthening of the underlying end-plate current, (ii) an increased membrane resistance and (iii) marked inward-going (anomalous) rectification of the muscle membrane.
D000818:Animals; D001001:Anura; D002462:Cell Membrane / Q000187:drug effects; D004553:Electric Conductivity; D004594:Electrophysiology; D009388:Neostigmine / Q000494:pharmacology; D009469:Neuromuscular Junction / Q000187:drug effects*; D012964:Sodium / Q000494:pharmacology*; D013779:Tetrodotoxin / Q000494:pharmacology
D009388:Neostigmine; D013779:Tetrodotoxin; D012964:Sodium